Soil salinization is an important abiotic factor affecting agricultural production in China, and the identification of salt tolerance-related genes/QTLs in rice is crucial for ensuring stable rice production in saline-alkali soils.
Aigela and Xudao 10, which exhibit significant differences in salt tolerance related traits, were used as parent plants to create a doubled haploid (DH) population. Salt tolerance was identified under field and hydroponic conditions. Genotyping of the targeted population was performed using the rice 1 K mGPS SNP chip. Phenotypic data combined with genotype data of DH population were used for QTL mapping with the QTL IciMapping 4.2 software.
Through QTL mapping analysis, a total of 22 salt tolerance related QTLs were detected, including 10 QTLs for grain yield per plant, 4 for grains per panicle, 2 for root length, and 6 for root dry weight. These QTLs are located on chromosomes 1, 6, 8, 10, 11, and 12, explaining phenotypic variation of 3.37%-15.52% with LOD values ranging from 4.04 to 9.65. Based on the gene annotation, Arabidopsis homologous gene comparison, spatiotemporal expression analysis and sequence comparison within the mapping interval of qST11, a candidate gene (LOC_Os11g30560) encoding a hydroxysteroid dehydrogenase (OsHSD1) was identified.
Among the 22 QTLs detected in this study, 11 were known genes or loci related to salt tolerance, and the remaining 11 were newly identified. Meanwhile, the candidate gene analysis was conducted on the newly identified salt tolerance QTL (qST11), laying a foundation for cloning of salt-tolerance related genes and deciphering their genetic regulatory networks.
| 科 Family | 属数 Number of genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) | 属 Genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) |
|---|---|---|---|---|---|---|
| 鹅膏菌科Amanitaceae | 2 | 11 | 5.26 | 鹅膏菌属 Amanita | 10 | 4.78 |
| 小菇科 Mycenaceae | 2 | 12 | 5.74 | 丝盖伞属 Inocybe | 5 | 2.39 |
| 多孔菌科 Polyporaceae | 8 | 14 | 6.70 | 蜡蘑属 Laccaria | 5 | 2.39 |
| 红菇科 Russulaceae | 3 | 23 | 11.00 | 小皮伞属 Marasmius | 6 | 2.87 |
| 小菇属 Mycena | 11 | 5.26 | ||||
| 光柄菇属 Pluteus | 5 | 2.39 | ||||
| 红菇属 Russula | 17 | 8.13 | ||||
| 栓菌属 Trametes | 5 | 2.39 |